You expect validation from a man that has no morals or character. The only failure you have is in your choice of men. It is not you that has made this marriage a failure, it is your husband. I am sorry that you chose to marry this man after so many affairs, but you did. Now you have to decide if you are willing to continue to put up with this type of behavior.
You don't need this man. You don't need him to validate you as a woman, wife, or mother. You are not the one that has no morals HE is. Obviously the women he has committed infidelity with have not more morals or character than HE has, as they would not be spreading their legs for a married man. Yes, this was not your friend that befriended you and slept with your husband. She is a harlot, just like the others.
You need to decide what kind of life you want for your daughter, and what kind of example you want to set for her, as she is going to one day grow up, and surely you don't want to send her a message that it is okay for this kind of behavior to take place, as well as sending her a message that she should accept this type of behavior from her husband.
You need to decide what you are willing to put up with. Your husband is a low life, no doubt, and you and your daughter deserve better. If you are not getting the emotional things you are needing from your husband, and he obviously is not going to change, get out now. You have not mentioned your age, but if you have a young daughter, I assume you are young yourself, and still have a lot of time to find someone that will show you the respect you deserve, and give you the romance you are needing.
Moving on is not going to be easy, but you can at least take solace in the fact that you always took the high road, and did your best to make the best of the marriage. You can take solace in the fact that you did the right thing and get out of a situation before your husband brings home a deadly disease that will make an orphan out of your daughter. It will not be easy, and the pain will take time to heal but it will heal.
You need to get out of the situation you are in, and focus on you and your daughter. You need to take time, maybe even counseling, to help you realize you are worth more than the treatment your husband has shown you. You need to focus on your self esteem and realize your true worth, which has nothing to do with your husband's view of you, your marriage, or the way he treats women. You have a daughter, and if you will focus on healing, and at the same time know that you are going to do everything you can to ensure your daughter does not allow a man to drag her down the way this man has done you, to the point to where you are looking to blame yourself, for an immoral man that lacks the character we of humankind still have.
I hope this at least gives you some food for thought. Good luck, and realize these boards can be a wealth of support while you are going through this transition, and taking back your life, and living it to the fullest, to a new adventure that will be your future.